Investigation of effects of diesurface angle, temperature and blank holderforce on the hardness distribution forming in material after deepdrawing process

Yıl 2018, Cilt: 6 Sayı: 3, 35 - 41, 30.09.2018

Cebeli Özek Vedat Taşdemir

https://doi.org/10.21541/apjes.376495

Cited By: 1

Öz

In this study, it is aimed to determine the effects of
die surface angle, temperature and blank holder force on the hardness of the
obtained cups by deep drawing method. In the study, 4 different die surface
angles (0°, 5°, 10°, 15°), four different temperatures (25^oC, 100^oC,
175^oC, 250^oC) and three different blank holder force
(1200 N, 2400 N, 3600 N) were used.  As a
result of the studies, it was determined that the hardness of the cups
decreased with the increase of the temperature, the hardness of the cups increased
with the increase of the blank holder force and the most ideal die surface
angle is 5-10° in terms of both hardness and forming. Moreover, it has been
observed that the lowest hardness in the obtained cups is at the bottom of the
cup and the hardness increases as moved towards the mouth of the cup. When the
limit drawing ratio increased from 2.14 to 2.75, there was no increase in
hardness due to the effect of temperature. As a result, it is clearly seen that
the determined parameters play an important role in controlling the hardness
during deformation.

Anahtar Kelimeler

Deep drawing, hardness distribution, die surface angle, limit drawing ration

Derin çekme işlemi sonrası malzemede oluşan sertlik dağılımı üzerine kalıp yüzey açısı, sıcaklık ve baskı plakası kuvveti etkilerinin incelenmesi

Öz

Bu çalışmada, derin çekme
yöntemi ile elde edilen kapların sertliğine kalıp yüzey açısı, sıcaklık ve
baskı plakası kuvvetinin etkilerinin belirlenmesi amaçlanmıştır. Çalışmada, 4
farklı kalıp yüzey açısı (0°, 5°, 10°, 15° ), 4 farklı sıcaklık(25°C, 100^oC,
175^oC, 250^oC) ve 3 farklı baskı plakası kuvveti (1200 N,
2400 N, 3600 N) kullanılmıştır. Yapılan deneyler sonucunda sıcaklığın
artmasıyla kapların sertliğinin düştüğü, baskı plakası kuvvetinin artması ile
kapların sertliğinin çok az arttığı ve hem sertlik hem de şekillendirme
açısından en ideal kalıp açısının 5-10° olduğu belirlenmiştir. Ayrıca elde
edilen kaplardaki en düşük sertliğin kap tabanında olduğu, kap ağzına doğru
çıkıldıkça sertliğin arttığı görülmüştür. Limit çekme oranı 2,14'den 2,75'e
çıktığında sıcaklığın etkisi ile sertlikte artış olmamıştır. Sonuç olarak,
belirlenen parametrelerin deformasyon sırasında oluşan sertliğin kontrolünde
önemli rol oynadığı net bir şekilde görülmüştür.

Anahtar Kelimeler

Derin çekme, sertlik dağılımı, kalıp yüzey açısı, limit çekme oranı

Kaynakça

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